This invention relates to a device for preventing movement of a vehicle under its own power when the seat is unoccupied and more paricularly to a device for automatically neutralizing a hydraulic drive arrangement when the driver gets off of the operator's seat.
The so called "dead man" controls have been employed for many years on all types of vehicles to stop the vehicle automatically if the operator gets off the seat. Such dead man controls include both mechanical and hydraulic apparatuses for applying vehicle brakes and both types of apparatuses have also been employed for disengaging a clutch in the drive line or transmission. However, heretofore such dead man controls have not been available for vehicles having a fluid drive train in which tractive power is transmitted to the wheels through a fluid drive motor which in turn is driven by pressurized fluid delivered from a fluid pump driven by the engine.